xref: /openbmc/u-boot/drivers/mmc/gen_atmel_mci.c (revision 699c40e8)
1 /*
2  * Copyright (C) 2010
3  * Rob Emanuele <rob@emanuele.us>
4  * Reinhard Meyer, EMK Elektronik <reinhard.meyer@emk-elektronik.de>
5  *
6  * Original Driver:
7  * Copyright (C) 2004-2006 Atmel Corporation
8  *
9  * See file CREDITS for list of people who contributed to this
10  * project.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of
15  * the License, or (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25  * MA 02111-1307 USA
26  */
27 
28 #include <common.h>
29 #include <mmc.h>
30 #include <part.h>
31 #include <malloc.h>
32 #include <asm/io.h>
33 #include <asm/errno.h>
34 #include <asm/byteorder.h>
35 #include <asm/arch/clk.h>
36 #include <asm/arch/hardware.h>
37 #include "atmel_mci.h"
38 
39 #ifndef CONFIG_SYS_MMC_CLK_OD
40 # define CONFIG_SYS_MMC_CLK_OD	150000
41 #endif
42 
43 #define MMC_DEFAULT_BLKLEN	512
44 
45 #if defined(CONFIG_ATMEL_MCI_PORTB)
46 # define MCI_BUS 1
47 #else
48 # define MCI_BUS 0
49 #endif
50 
51 static int initialized = 0;
52 
53 /*
54  * Print command and status:
55  *
56  * - always when DEBUG is defined
57  * - on command errors
58  */
59 static void dump_cmd(u32 cmdr, u32 arg, u32 status, const char* msg)
60 {
61 	printf("gen_atmel_mci: CMDR %08x (%2u) ARGR %08x (SR: %08x) %s\n",
62 		cmdr, cmdr&0x3F, arg, status, msg);
63 }
64 
65 /* Setup for MCI Clock and Block Size */
66 static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen)
67 {
68 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
69 	u32 bus_hz = get_mci_clk_rate();
70 	u32 clkdiv = 255;
71 
72 	debug("mci: bus_hz is %u, setting clock %u Hz, block size %u\n",
73 		bus_hz, hz, blklen);
74 	if (hz > 0) {
75 		/* find lowest clkdiv yielding a rate <= than requested */
76 		for (clkdiv=0; clkdiv<255; clkdiv++) {
77 			if ((bus_hz / (clkdiv+1) / 2) <= hz)
78 				break;
79 		}
80 	}
81 	printf("mci: setting clock %u Hz, block size %u\n",
82 		(bus_hz / (clkdiv+1)) / 2, blklen);
83 
84 	blklen &= 0xfffc;
85 	/* On some platforms RDPROOF and WRPROOF are ignored */
86 	writel((MMCI_BF(CLKDIV, clkdiv)
87 		 | MMCI_BF(BLKLEN, blklen)
88 		 | MMCI_BIT(RDPROOF)
89 		 | MMCI_BIT(WRPROOF)), &mci->mr);
90 	/*
91 	 * On some new platforms BLKLEN in mci->mr is ignored.
92 	 * Should use the BLKLEN in the block register.
93 	 */
94 	writel(MMCI_BF(BLKLEN, blklen), &mci->blkr);
95 	initialized = 1;
96 }
97 
98 /* Return the CMDR with flags for a given command and data packet */
99 static u32 mci_encode_cmd(
100 	struct mmc_cmd *cmd, struct mmc_data *data, u32* error_flags)
101 {
102 	u32 cmdr = 0;
103 
104 	/* Default Flags for Errors */
105 	*error_flags |= (MMCI_BIT(DTOE) | MMCI_BIT(RDIRE) | MMCI_BIT(RENDE) |
106 		MMCI_BIT(RINDE) | MMCI_BIT(RTOE));
107 
108 	/* Default Flags for the Command */
109 	cmdr |= MMCI_BIT(MAXLAT);
110 
111 	if (data) {
112 		cmdr |= MMCI_BF(TRCMD, 1);
113 		if (data->blocks > 1)
114 			cmdr |= MMCI_BF(TRTYP, 1);
115 		if (data->flags & MMC_DATA_READ)
116 			cmdr |= MMCI_BIT(TRDIR);
117 	}
118 
119 	if (cmd->resp_type & MMC_RSP_CRC)
120 		*error_flags |= MMCI_BIT(RCRCE);
121 	if (cmd->resp_type & MMC_RSP_136)
122 		cmdr |= MMCI_BF(RSPTYP, 2);
123 	else if (cmd->resp_type & MMC_RSP_BUSY)
124 		cmdr |= MMCI_BF(RSPTYP, 3);
125 	else if (cmd->resp_type & MMC_RSP_PRESENT)
126 		cmdr |= MMCI_BF(RSPTYP, 1);
127 
128 	return cmdr | MMCI_BF(CMDNB, cmd->cmdidx);
129 }
130 
131 /* Entered into function pointer in mci_send_cmd */
132 static u32 mci_data_read(atmel_mci_t *mci, u32* data, u32 error_flags)
133 {
134 	u32 status;
135 
136 	do {
137 		status = readl(&mci->sr);
138 		if (status & (error_flags | MMCI_BIT(OVRE)))
139 			goto io_fail;
140 	} while (!(status & MMCI_BIT(RXRDY)));
141 
142 	if (status & MMCI_BIT(RXRDY)) {
143 		*data = readl(&mci->rdr);
144 		status = 0;
145 	}
146 io_fail:
147 	return status;
148 }
149 
150 /* Entered into function pointer in mci_send_cmd */
151 static u32 mci_data_write(atmel_mci_t *mci, u32* data, u32 error_flags)
152 {
153 	u32 status;
154 
155 	do {
156 		status = readl(&mci->sr);
157 		if (status & (error_flags | MMCI_BIT(UNRE)))
158 			goto io_fail;
159 	} while (!(status & MMCI_BIT(TXRDY)));
160 
161 	if (status & MMCI_BIT(TXRDY)) {
162 		writel(*data, &mci->tdr);
163 		status = 0;
164 	}
165 io_fail:
166 	return status;
167 }
168 
169 /*
170  * Entered into mmc structure during driver init
171  *
172  * Sends a command out on the bus and deals with the block data.
173  * Takes the mmc pointer, a command pointer, and an optional data pointer.
174  */
175 static int
176 mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
177 {
178 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
179 	u32 cmdr;
180 	u32 error_flags = 0;
181 	u32 status;
182 
183 	if (!initialized) {
184 		puts ("MCI not initialized!\n");
185 		return COMM_ERR;
186 	}
187 
188 	/* Figure out the transfer arguments */
189 	cmdr = mci_encode_cmd(cmd, data, &error_flags);
190 
191 	/* For multi blocks read/write, set the block register */
192 	if ((cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK)
193 			|| (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK))
194 		writel(data->blocks | MMCI_BF(BLKLEN, mmc->read_bl_len),
195 			&mci->blkr);
196 
197 	/* Send the command */
198 	writel(cmd->cmdarg, &mci->argr);
199 	writel(cmdr, &mci->cmdr);
200 
201 #ifdef DEBUG
202 	dump_cmd(cmdr, cmd->cmdarg, 0, "DEBUG");
203 #endif
204 
205 	/* Wait for the command to complete */
206 	while (!((status = readl(&mci->sr)) & MMCI_BIT(CMDRDY)));
207 
208 	if (status & error_flags) {
209 		dump_cmd(cmdr, cmd->cmdarg, status, "Command Failed");
210 		return COMM_ERR;
211 	}
212 
213 	/* Copy the response to the response buffer */
214 	if (cmd->resp_type & MMC_RSP_136) {
215 		cmd->response[0] = readl(&mci->rspr);
216 		cmd->response[1] = readl(&mci->rspr1);
217 		cmd->response[2] = readl(&mci->rspr2);
218 		cmd->response[3] = readl(&mci->rspr3);
219 	} else
220 		cmd->response[0] = readl(&mci->rspr);
221 
222 	/* transfer all of the blocks */
223 	if (data) {
224 		u32 word_count, block_count;
225 		u32* ioptr;
226 		u32 sys_blocksize, dummy, i;
227 		u32 (*mci_data_op)
228 			(atmel_mci_t *mci, u32* data, u32 error_flags);
229 
230 		if (data->flags & MMC_DATA_READ) {
231 			mci_data_op = mci_data_read;
232 			sys_blocksize = mmc->read_bl_len;
233 			ioptr = (u32*)data->dest;
234 		} else {
235 			mci_data_op = mci_data_write;
236 			sys_blocksize = mmc->write_bl_len;
237 			ioptr = (u32*)data->src;
238 		}
239 
240 		status = 0;
241 		for (block_count = 0;
242 				block_count < data->blocks && !status;
243 				block_count++) {
244 			word_count = 0;
245 			do {
246 				status = mci_data_op(mci, ioptr, error_flags);
247 				word_count++;
248 				ioptr++;
249 			} while (!status && word_count < (data->blocksize/4));
250 #ifdef DEBUG
251 			if (data->flags & MMC_DATA_READ)
252 			{
253 				printf("Read Data:\n");
254 				print_buffer(0, data->dest, 1,
255 					word_count*4, 0);
256 			}
257 #endif
258 #ifdef DEBUG
259 			if (!status && word_count < (sys_blocksize / 4))
260 				printf("filling rest of block...\n");
261 #endif
262 			/* fill the rest of a full block */
263 			while (!status && word_count < (sys_blocksize / 4)) {
264 				status = mci_data_op(mci, &dummy,
265 					error_flags);
266 				word_count++;
267 			}
268 			if (status) {
269 				dump_cmd(cmdr, cmd->cmdarg, status,
270 					"Data Transfer Failed");
271 				return COMM_ERR;
272 			}
273 		}
274 
275 		/* Wait for Transfer End */
276 		i = 0;
277 		do {
278 			status = readl(&mci->sr);
279 
280 			if (status & error_flags) {
281 				dump_cmd(cmdr, cmd->cmdarg, status,
282 					"DTIP Wait Failed");
283 				return COMM_ERR;
284 			}
285 			i++;
286 		} while ((status & MMCI_BIT(DTIP)) && i < 10000);
287 		if (status & MMCI_BIT(DTIP)) {
288 			dump_cmd(cmdr, cmd->cmdarg, status,
289 				"XFER DTIP never unset, ignoring");
290 		}
291 	}
292 
293 	return 0;
294 }
295 
296 /* Entered into mmc structure during driver init */
297 static void mci_set_ios(struct mmc *mmc)
298 {
299 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
300 	int busw = (mmc->bus_width == 4) ? 1 : 0;
301 
302 	/* Set the clock speed */
303 	mci_set_mode(mmc, mmc->clock, MMC_DEFAULT_BLKLEN);
304 
305 	/*
306 	 * set the bus width and select slot for this interface
307 	 * there is no capability for multiple slots on the same interface yet
308 	 * Bitfield SCDBUS needs to be expanded to 2 bits for 8-bit buses
309 	 */
310 	writel(MMCI_BF(SCDBUS, busw) | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
311 }
312 
313 /* Entered into mmc structure during driver init */
314 static int mci_init(struct mmc *mmc)
315 {
316 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
317 
318 	/* Initialize controller */
319 	writel(MMCI_BIT(SWRST), &mci->cr);	/* soft reset */
320 	writel(MMCI_BIT(PWSDIS), &mci->cr);	/* disable power save */
321 	writel(MMCI_BIT(MCIEN), &mci->cr);	/* enable mci */
322 	writel(MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);	/* select port */
323 
324 	/* This delay can be optimized, but stick with max value */
325 	writel(0x7f, &mci->dtor);
326 	/* Disable Interrupts */
327 	writel(~0UL, &mci->idr);
328 
329 	/* Set default clocks and blocklen */
330 	mci_set_mode(mmc, CONFIG_SYS_MMC_CLK_OD, MMC_DEFAULT_BLKLEN);
331 
332 	return 0;
333 }
334 
335 /*
336  * This is the only exported function
337  *
338  * Call it with the MCI register base address
339  */
340 int atmel_mci_init(void *regs)
341 {
342 	struct mmc *mmc = malloc(sizeof(struct mmc));
343 
344 	if (!mmc)
345 		return -1;
346 	strcpy(mmc->name, "mci");
347 	mmc->priv = regs;
348 	mmc->send_cmd = mci_send_cmd;
349 	mmc->set_ios = mci_set_ios;
350 	mmc->init = mci_init;
351 	mmc->getcd = NULL;
352 
353 	/* need to be able to pass these in on a board by board basis */
354 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
355 	mmc->host_caps = MMC_MODE_4BIT;
356 	/*
357 	 * min and max frequencies determined by
358 	 * max and min of clock divider
359 	 */
360 	mmc->f_min = get_mci_clk_rate() / (2*256);
361 	mmc->f_max = get_mci_clk_rate() / (2*1);
362 
363 	mmc->b_max = 0;
364 
365 	mmc_register(mmc);
366 
367 	return 0;
368 }
369